JPH0145154Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to microwave low noise semiconductor devices consisting of discrete microwave transistor chips and monolithic integrated circuits.

Conventionally, microwave low-noise semiconductor devices made of microwave transistors such as microwave transistor low-noise amplifiers have been constructed from so-called hybrid integrated circuits in which input and output impedance matching circuits are formed on ceramic substrates using individual transistors. However, in recent years, with the advancement of gallium arsenide (GaAs) monolithic integrated circuit technology, microwave monolithic integrated circuits such as microwave GaAs field effect transistors and monolithic amplifiers have been developed. It is expected to bring about effects such as miniaturization, improved reliability due to fewer assembly processes, uniform quality due to mass production, and lower prices.

However, the drawbacks of microwave monolithic integrated circuits are that compared to hybrid integrated circuits, they are constructed with finer circuit patterns and therefore have higher circuit loss, that it is more difficult to reduce the noise of the transistors themselves than with individual transistors, and that circuit adjustment is not possible. In addition, when realizing products with a wide variety of characteristic specifications, production costs increase and it is difficult to support high-mix, low-volume production. Circuit losses, the characteristics of the transistors themselves, and the possibility of circuit adjustment become extremely important issues when the required characteristics are strict, and when the characteristics can be achieved in hybrid circuits using individual transistors, but not in monolithic integrated circuits. occurs. This hinders the realization of low-cost, mass-production technology for microwave devices through monolithic construction. Note that even in hybrid integrated circuits, when the frequency is high, the package that houses the transistor chips has an effect on the characteristics, making it difficult to achieve high performance.

An object of the present invention is to provide a microwave low-noise semiconductor device that solves the above-mentioned problems, has excellent low-noise characteristics, can be manufactured at low cost, and can be mass-produced.

According to the present invention, a microwave input stage low-noise amplifier circuit is constructed by providing an impedance matching circuit directly on the chip of individual microwave low-noise transistors, and a microwave circuit cascade-connected to the input stage low-noise amplifier circuit is configured. A microwave low-noise semiconductor device characterized in that it is constituted by a monolithic integrated circuit is obtained. In microwave low-noise semiconductor devices, the characteristics of the device are mostly determined by the noise characteristics of the input stage, but in this invention, an impedance matching circuit is provided directly on the transistor chip to avoid the effects of the package and reduce circuit loss. The input stage amplifier circuit is constructed using a hybrid integrated circuit that can be made small, and the noise of the input stage amplifier circuit is reduced. At the same time, the microwave circuits in the next stage and subsequent stages, whose noise characteristics are not as severe as those of the input stage, are constructed using monolithic integrated circuits. It has the characteristics of enabling mass production and lower prices. According to the present invention, the effect is remarkable in microwave low-noise semiconductor devices that require low noise characteristics, mass production, and low cost, especially in ultra-high frequency low-noise devices of 10 _GHZ or higher.

The present invention will be explained in detail below using the drawings.

FIG. 1 is a plan view for explaining a microwave low noise gallium arsenide field effect transistor amplifier which is an embodiment of the present invention. In FIG. 1, a source-grounded microwave low-noise GaAs field effect transistor chip 1 is brazed and fixed to a base block 3 which also serves as a ground conductor of a ceramic package 2, and the gate electrode of the transistor 1 is formed on the ceramic substrate. The drain electrode of the transistor 1 is connected by a bonding wire to an input impedance matching circuit 4 consisting of a microstrip line formed on a ceramic substrate, and an output impedance matching circuit 5 consisting of a microstrip line formed on a ceramic substrate. , a DC voltage is applied to the gate electrode and the drain electrode through package leavers 6 and 7, bypass chip capacitors 8 and 9, and bias circuits 10 and 11 on the ceramic substrate, respectively, and the output impedance matching circuit 5 includes a DC blocking chip capacitor. 12 to the input pad of a GaAs monolithic integrated circuit chip 13 of a two-stage GaAs field effect transistor amplifier. DC voltage supply to the gate and drain electrodes of the monolithic amplifier takes place through leads 14 and 15 provided on the package and supporting substrates 16 and 17, respectively. The microwave bypass capacitor is constructed in a monolithic integrated circuit. The microwave input signal to the amplifier is applied to the input impedance matching circuit 4 of the transistor 1 through a lead 18 provided on the package, and the output signal is taken out from the lead 19 of the package connected to the output take-out pad of the monolithic integrated circuit chip 13. It will be done. The ceramic package is hermetically sealed with a cap. FIG. 2 is a block diagram showing the structure of the circuit and package of the embodiment shown in FIG. In the figure, the package 22 is equipped with an input impedance matching circuit 24 and an output impedance matching circuit 25.
A GaAs amplifier monolithic integrated circuit chip 33 has a two-stage configuration consisting of a GaAs field effect transistor chip 21, and field effect transistors 34 and 35 having an input impedance matching circuit 40, an interstage impedance matching circuit 41, and an output impedance matching circuit 42. Be prepared. 38 and 3
9 represents the input and output terminals of the amplifier.

According to this invention, the input stage low-noise amplifier circuit, which has the greatest influence on the noise characteristics of the amplifier, is
By using a configuration in which an impedance matching circuit is provided directly on a GaAs field-effect transistor chip, good low-noise characteristics can be easily achieved, and the subsequent stage circuits, where requirements for noise characteristics are not as strict as the input stage, can be monolithically integrated. It is composed of circuits, which improves productivity and reduces costs.
Such effects make it difficult to achieve low noise characteristics.
This is noticeable in semiconductor devices such as low-noise amplifiers of 10 _GHZ or higher.

FIG. 3 is a block diagram showing the configuration of a circuit and a package for explaining a microwave low noise GaAs field effect transistor amplifier which is another embodiment of the present invention. In FIG. 3, microwave input terminal 48 and output terminal 4
A low-noise GaAs field effect transistor chip 21 having an input impedance matching circuit 24 and an output impedance matching circuit 25 is housed inside a first package 52 having an input impedance matching circuit 8'.
An input impedance matching circuit 40, an interstage impedance matching circuit 41, and an output impedance matching circuit 42 are provided inside a second package 53 having an input terminal 49' and an output terminal 49 connected to the output terminal of the package 52. A two-stage structure consisting of field effect transistors 34 and 35.
It houses a GaAs amplifier monolithic integrated circuit chip 33. This example is a microwave low noise semiconductor device having a structure in which a hybrid integrated circuit is housed in a first package and a monolithic integrated circuit is housed in a second package.By dividing the structure, each package part can be measured independently. Since this can be evaluated, it is possible to further improve the characteristics, and when combined with the characteristics shown in the first embodiment, the effect becomes even more remarkable.

In addition, in this example, microwave low noise
Although we explained about GaAs field effect transistor amplifiers, transistors are not limited to GaAs field effect transistors, and the frequency range is not limited to a specific range.
It may be in the UHF band, millimeter wave band, etc. It goes without saying that the circuit function of the monolithic integrated circuit is not limited to an amplifier circuit, but may also be a mixer, or a circuit including an amplifier, mixer, oscillator, etc. The configuration of the impedance matching circuit of the input stage amplifier may also be a lumped element circuit or the like, and is not limited to a specific circuit type or material.

[Brief explanation of the drawing]

FIG. 1 is a plan view for explaining a microwave low noise GaAs field effect transistor amplifier which is an embodiment of the present invention. FIG. 2 is a block diagram showing the structure of the circuit and package of the embodiment shown in FIG. FIG. 3 is a block diagram showing the circuit and package configuration of a microwave low noise GaAs field effect transistor amplifier, which is another embodiment of the present invention. In the figure, 1 and 21 are microwave low noise
GaAs field effect transistor chip, 2,2
2, 52 and 53 are packages; 4 and 24 are input impedance matching circuits for the transistor chips 1 and 21 respectively; 5 and 25 are output impedance matching circuits; 13 and 33 are GaAs monolithic integrated GaAs field effect transistor two-stage amplifiers. Circuit chips 34 and 35 are GaAs field effect transistors constituting a GaAs monolithic integrated circuit, and 40, 41 and 42 are GaAs field effect transistors, respectively.
Input, interstage and output impedance matching circuits constituting the monolithic integrated circuit, 38 and 48 indicate input terminals of the amplifier, and 39 and 49 indicate output terminals of the amplifier.

Claims (1)

[Scope of utility model registration request] A microwave input stage low-noise amplifier circuit consisting of a hybrid integrated circuit in which an impedance matching circuit is provided directly on the chip of individual microwave low-noise transistors, and a monolithic integrated circuit type micrometer connected in cascade to the input stage low-noise amplifier circuit. A microwave low-noise semiconductor device comprising a wave circuit.